Printing device production method

Abstract

The invention provides a printing device production method for producing a printing device in which a printing part is adjusted with high precision, and the printing device production method is used for producing an adjusted printing device from a printing device before adjustment of a serial ink jet system, a first mark A and a first mark B are printed on an inspection sheet by using a first nozzle group, a second mark A and a second mark B are printed by using a second nozzle group, and the distance between the first mark A and the first mark B is different from the distance between any two marks except the combination of the first mark A and the first mark B; the distance between the second identifier A and the second identifier B is different from the distance between any two identifiers except the combination of the second identifier A and the second identifier B. In the analysis, which identifier is detected is distinguished based on the distance between the two identifiers; and determines the position of the inspection pattern on the inspection sheet on the basis of the positions of the two identified marks.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a printing device. Background Art

[0002] Conventionally, a technique for detecting printing errors by scanning a printing medium printed with a specific inspection pattern has been known. In Patent Document 1, a technique for accurately determining the size, position, and inclination of an adjustment pattern (inspection pattern) is disclosed.

[0003] On an inspection sheet, inspection patterns for correcting printing errors such as medium conveyance offset (PF offset, Paper Feed offset) and offset of dot formation positions (Bi-D) caused by relative position movement during reciprocation in the main scanning direction between a printing unit and the medium are printed. Also, there are cases where it is desired to use the inspection pattern to confirm the presence or absence of nozzle clogging. In such a case, the inspection sheet includes an inspection pattern for inspecting nozzle clogging. In a state where nozzle clogging has not been eliminated, it is not possible to accurately print an inspection pattern for correcting other printing errors. Therefore, it is desired to reliably detect the inspection pattern for nozzle clogging.

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2023-119715 Summary of the Invention

[0005] In view of the above problems, the present invention relates to a method for manufacturing a printing device, the method for manufacturing a printing device includes printing an inspection sheet including an inspection pattern with a pre-adjustment printing device of a serial inkjet method, causing a scanning unit to read the inspection sheet, and adjusting the pre-adjustment printing device based on the inspection pattern detected by analyzing the read inspection sheet, thereby manufacturing an adjusted printing device. In the method for manufacturing a printing device, a first A mark and a first B mark are printed on the inspection sheet using a first nozzle group, and a second A mark and a second B mark are printed using a second nozzle group. The distance between the first A mark and the first B mark is different from the distance between any two marks other than the combination of the first A mark and the first B mark. The distance between the second A mark and the second B mark is different from the distance between any two marks other than the combination of the second A mark and the second B mark. In the analysis, which mark is detected is discriminated based on the distance between two marks detected from the inspection sheet, and the position of the inspection pattern on the inspection sheet is determined based on the positions of the discriminated two marks. Brief Description of the Drawings

[0006] Figure 1It is a structural diagram of a multi-functional machine.

[0007] Figure 2 It is a diagram showing the positional relationship between the scanning unit and the medium.

[0008] Figure 3 It is a diagram showing the inspection sheet.

[0009] Figure 4 It is an explanatory diagram of the nozzle array and the nozzle identification.

[0010] Figure 5 It is a diagram showing the distance between the identifications.

[0011] Figure 6 It is an explanatory diagram of the detection process of the identification group.

[0012] Figure 7 It is an explanatory diagram of the detection process of the identification group.

[0013] Figure 8 It is a flowchart showing the printing process of the inspection sheet.

[0014] Figure 9 It is a flowchart showing the reading process of the inspection sheet.

[0015] Figure 10 It is an explanatory diagram of the nozzle array and the nozzle identification related to the second embodiment.

[0016] Figure 11 is a diagram showing the distance between the identifications.

[0017] Figure 12 It is an explanatory diagram of the detection process of the identification group.

[0018] Figure 13 is an explanatory diagram of the detection process of the identification group.

[0019] Figure 14 It is an explanatory diagram of the nozzle array and the nozzle identification related to the modification example. Specific embodiments

[0020] First embodiment

[0021] Figure 1 It is a structural diagram of the multi-functional machine 10 related to the first embodiment. The multi-functional machine 10 has a printing function and a scanner function. In addition, the multi-functional machine 10 may also have functions other than the above functions such as FAX. The multi-functional machine 10 is an example of a printing device. The multi-functional machine 10 includes a printing unit 11, a scanning unit 12, a processor 13, a non-volatile memory 14, a UI unit 15, a communication unit 16, and a cleaning unit 17. The printing unit 11 includes a print head 111, a carriage 112, and a conveying mechanism 113.

[0022] The compound machine 10 of the present embodiment is configured as an apparatus for performing monochromatic printing. The print head 111 includes a nozzle array corresponding to black (K) ink, and performs printing in a serial inkjet manner. The nozzle array includes a plurality of nozzles, and ink is ejected from each nozzle. The ink for each nozzle is supplied from an ink tank (not shown) or the like. By ejecting ink from each nozzle of the print head 111, droplets (dots) of ink are formed on a medium (paper).

[0023] The print head 111 is mounted on a carriage 112. The carriage 112 reciprocates in a specific direction under the control of a processor 13. Accordingly, the print head 111 reciprocates in a specific direction. The direction in which the print head 111 reciprocates is referred to as the main scanning direction. The conveyance mechanism 113 is a device for conveying a medium to be printed. The conveyance mechanism 113 conveys the paper in a direction perpendicular to the main scanning direction of the print head 111. Here, the direction perpendicular to the main scanning direction of the print head 111, that is, the direction in which the paper is conveyed, is referred to as the sub-scanning direction.

[0024] In the nozzle array of the print head 111, a plurality of nozzles are arranged at equal intervals in the sub-scanning direction. By repeatedly ejecting ink from the nozzles during the reciprocating movement of the print head 111 and conveying the medium by the conveyance mechanism 113, printing on the medium is performed. The cleaning unit 17 cleans the ink clogging of the nozzles by sucking ink.

[0025] The scanning unit 12 includes a light source and a light receiving element that receives light from an object to be scanned. In the scanning unit 12 of the present embodiment, a CMOS (Complementary Metal Oxide Semiconductor) line sensor using a CIS (Contact Image Sensor) method is used. In addition, as another example, the scanning unit 12 may also be a sensor using a CCD (Charge Coupled Device) method. Hereinafter, the arrangement direction of the light receiving elements in the line sensor is referred to as the main scanning direction of the scanning unit 12.

[0026] As Figure 2As shown, the multifunction machine 10 includes a media table 122 provided with a glass surface 121 on which the object P to be read is placed. That is, the multifunction machine 10 includes a flatbed scanning device, which includes a scanning unit 12, a glass surface 121, and a media table 122. Under the control of the processor 13, the scanning unit 12 moves on the glass surface 121 in a direction B perpendicular to the main scanning direction A. Hereinafter, the direction perpendicular to the main scanning direction is referred to as the sub-scanning direction of the scanning unit 12. The scanning unit 12 reads the entire object P by repeatedly reading while moving at a predetermined amount in the sub-scanning direction.

[0027] In the present embodiment, the relative position of the object P and the scanning unit 12 is changed by moving the scanning unit 12 relative to the placed object P. However, as another example, it may be configured that the relative position is changed by conveying the medium in the sub-scanning direction with respect to the fixed scanning unit 12 using the conveying mechanism 113.

[0028] The processor 13 includes a RAM (Random Access Memory) and a CPU (Central Processing Unit), etc. The non-volatile memory 14 stores various data and programs. The processor 13 can execute the programs stored in the non-volatile memory 14. The UI unit 15 includes an input unit for accepting user input and a display unit for displaying various information to the user. The communication unit 16 communicates with external devices such as a PC or a tablet terminal connected by wired communication or wireless communication, etc.

[0029] In the multifunction machine 10 of the present embodiment, the printing unit 11 prints an inspection pattern on the medium. Here, the inspection pattern is an image showing a predetermined texture at a predetermined position. The multifunction machine 10 can adjust the control content of the printing unit 11 by scanning the inspection sheet printed with the inspection pattern and performing image analysis. Examples of the adjustment include correction of media conveyance offset (PF offset, Paper Feed offset), correction of dot formation position offset (Bi-D) caused by relative position movement during the round trip of the printing unit 11 and the medium in the main scanning direction, etc. In addition, the object of adjustment is not limited to the embodiment as long as it can be adjusted based on the inspection pattern. For example, in the present embodiment, the inspection pattern also includes a nozzle inspection pattern for confirming the presence or absence of nozzle clogging. When nozzle clogging is detected based on the nozzle inspection pattern, cleaning performed by the cleaning unit 17 is performed as an adjustment of the printing unit 11.

[0030] The processor 13 of the present embodiment includes a printing control unit 131, a scanning control unit 132, a detection unit 133, and an adjustment unit 134 as functional structures for adjusting the settings of the printing unit 11 using a check pattern. The functions of the printing control unit 131, the scanning control unit 132, the detection unit 133, and the adjustment unit 134 are realized by the processor 13 reading a program stored in the non-volatile memory 14 and executing the program. That is, hereinafter, the processes described as the processes executed by the printing control unit 131, the scanning control unit 132, the detection unit 133, and the adjustment unit 134 are the processes executed by the processor 13.

[0031] The printing control unit 131 controls the printing unit 11. The scanning control unit 132 controls the scanning unit 12. The detection unit 133 detects a predefined mark or check pattern in the scanned image. The detection unit 133 also performs matching by comparing the detected mark and check pattern with the corresponding reference mark and reference pattern, respectively. In addition, the reference mark and reference pattern referred to in the matching process are stored in the non-volatile memory 14 in advance. The adjustment unit 134 adjusts the settings of the printing unit 11 based on the detection result obtained by the detection unit 133.

[0032] Figure 3 It is a diagram showing an example of a check sheet. The print head 111 prints a check pattern on the check sheet 200 under the control of the printing control unit 131. In addition, in the check sheet 200, the side that is printed first among the sides parallel to the main scanning direction is called the upper side, and the other side is called the lower side. Further, among the sides parallel to the sub-scanning direction, when the check sheet 200 with the upper side positioned above is viewed from the front, the right side is called the right side, and the other side is called the left side.

[0033] On the check sheet 200, a nozzle check pattern 210 for confirming the presence or absence of nozzle clogging and other check patterns 221 to 223 are printed. The nozzle check pattern 210 is a pattern for confirming the presence or absence and degree of nozzle clogging. The other check patterns 221 to 223 are patterns for adjusting control contents such as the above-described medium conveyance deviation or dot formation position deviation.

[0034] At the upper part of the inspection sheet 200, a plurality of nozzle identification marks 231 to 238 are also printed as identification marks for determining the position of the nozzle inspection pattern 210. Near the nozzle inspection pattern 210, a plurality of position and inclination identification marks 251 to 254 are printed for correcting the position and inclination of the nozzle inspection pattern 210. In addition, near the other inspection pattern 221, a plurality of position and inclination identification marks 261 to 264 are printed for determining the position of the other inspection pattern 221. Similarly, near the other inspection patterns 222 and 223, position and inclination identification marks 271 to 276 are also printed. Image data of these nozzle identification marks 231 to 238, the nozzle inspection pattern 210, the other inspection patterns 221 to 223, and the position and inclination identification marks 251 to 254, 261 to 264, 271 to 276 are pre-stored in the non-volatile memory 14. Additionally, as another example, it can be set that these image data are stored in an external device and sent from the external device to the multifunction machine 10.

[0035] The nozzle identification marks 231 to 238 are arranged at predetermined relative positions with respect to the nozzle inspection pattern 210 in such a manner that their position relationships are known. Specifically, the nozzle identification marks 231 to 234 are printed in the left region 241 which is above and to the left (edge side) compared to the nozzle inspection pattern 210. The nozzle identification marks 234 to 238 are printed in the right region 242 which is above and to the right (edge side) compared to the nozzle inspection pattern 210.

[0036] Both the left region 241 and the right region 242 are arranged at the edge side in the left-right direction of the inspection sheet 200 compared to the nozzle inspection pattern 210 and the other inspection patterns 221 to 223. That is, the nozzle identification marks 231 to 238 are all printed at the edge side in the left-right direction of the inspection sheet 200 compared to the nozzle inspection pattern 210 and the other inspection patterns 221 to 223. Thus, by arranging each of the nozzle identification marks 231 to 238 at the edge side, the accuracy of position detection using the nozzle identification marks 231 to 238 can be improved. Additionally, the nozzle identification marks 231 to 238 may not be printed at the edge side compared to the position and inclination identification marks 251 to 254, 261 to 264, 271 to 276.

[0037] The four position inclination marks 251 to 254 are respectively arranged at different positions relative to the nozzle inspection pattern 210. Specifically, the position inclination marks 251 to 254 are arranged at the vertices of a rectangle with the main scanning direction and the sub-scanning direction as two sides on the outside of the nozzle inspection pattern 210. In this way, the four position inclination marks 251 to 254 are arranged in such a manner as to form a rectangle with a known size.

[0038] Moreover, the relationship (relative position relationship) between the position of the position inclination mark 251 and the upper left vertex of the nozzle inspection pattern 210 is preset. Therefore, the processor 13 can perform pattern detection of the nozzle inspection pattern 210 using the position of the position inclination mark 251 as a marker.

[0039] And, the relationship (relative position relationship) between the position of the position inclination mark 251 and the upper left vertex of the nozzle inspection pattern 210 is preset. Therefore, the processor 13 can perform pattern detection of the nozzle inspection pattern 210 using the position of the position inclination mark 251 as a marker. In addition, as described above, the processor 13 determines the presence or absence of deformation, inclination, etc. on the scanned image based on the sizes of the four position inspection marks in the shape of a rectangle and the size of the known rectangle, and thus can perform appropriate correction. Similarly, position inclination marks 271 to 276 are arranged around the other inspection patterns 221 to 223, and the other inspection patterns 222 and 223 are detected based on these position inclination marks, so that appropriate correction can be performed.

[0040] Figure 4 It is an explanatory diagram of the nozzle columns and the nozzle identification marks 231 to 238. In the present embodiment, the nozzle identification marks 231 to 238 are all in the shape of double circles and have the same size and the same shape.

[0041] As described above, the nozzle identification marks 231 to 238 are printed by being divided into the left region 241 and the right region 242 of the inspection sheet 200. In addition, each of the nozzle identification marks 231 to 238 is printed by a specific nozzle group. In the present embodiment, the multiple nozzles 301 included in the nozzle column 300 of the print head 111 are divided into four nozzle groups (the first nozzle group 311 to the fourth nozzle group 314), and one nozzle identification mark in the left region 241 and one nozzle identification mark in the right region 242 are printed by the same nozzle group.

[0042] In this embodiment, the multiple nozzles 301 are divided into four nozzle groups: a first nozzle group 311, a second nozzle group 312, a third nozzle group 313, and a fourth nozzle group 314. Each nozzle group includes nozzles that are different from each other. In this embodiment, among the 16 nozzles, the first to fourth nozzles are included in the first nozzle group 311, the fifth to eighth nozzles are included in the second nozzle group 312, the ninth to twelfth nozzles are included in the third nozzle group 313, and the thirteenth to sixteenth nozzles are included in the fourth nozzle group 314. Although several nozzles can belong to multiple nozzle groups, it is preferable that there are no nozzles that belong to multiple nozzle groups in a shared manner as in this embodiment.

[0043] Then, one nozzle identification for the left region 241 and one nozzle identification for the right region 242 are printed by each nozzle group. Hereinafter, the combination of one nozzle identification for the left region 241 and one nozzle identification for the right region 242 that are printed by the same nozzle group is referred to as an identification group.

[0044] In this embodiment, first, the nozzle identifications 231 and 238 are printed by the first nozzle group 311. Then, paper feeding is performed, and the nozzle identifications 232 and 237 are printed by the second nozzle group 312. Then, paper feeding is performed, and the nozzle identifications 233 and 236 are printed by the third nozzle group 313. Then, paper feeding is performed, and the nozzle identifications 234 and 235 are printed by the fourth nozzle group 314.

[0045] Hereinafter, for the sake of convenience of explanation, the nozzle identifications 231 and 238 printed by the first nozzle group 311 are respectively referred to as a first A identification and a first B identification, and they are referred to as a first identification group. In addition, the nozzle identifications 232 and 237 printed by the second nozzle group 312 are respectively referred to as a second A identification and a second B identification, and they are referred to as a second identification group. In addition, the nozzle identifications 233 and 236 printed by the third nozzle group 313 are respectively referred to as a third A identification and a third B identification, and they are referred to as a third identification group. In addition, the nozzle identifications 234 and 235 printed by the fourth nozzle group 314 are respectively referred to as a fourth A identification and a fourth B identification, and they are referred to as a fourth identification group.

[0046] Moreover, in the present embodiment, the printing unit 11 prints the two nozzle identification marks included in the same identification group in the same cycle. That is, the printing unit 11 prints the first A identification mark and the first B identification mark in the same cycle, and prints the second A identification mark and the second B identification mark in the same cycle. Moreover, the printing unit 11 prints the third A identification mark and the third B identification mark in the same cycle, and prints the fourth A identification mark and the fourth B identification mark in the same cycle. Thereby, it is possible to prevent the positions of the two nozzle identification marks in the same identification group from shifting in the sub-scanning direction due to different cycles.

[0047] In addition, in the present embodiment, the printing unit 11 prints all the identification marks (the first A identification mark, the first B identification mark, the second A identification mark, the second B identification mark, the third A identification mark, the third B identification mark, the fourth A identification mark, the fourth B identification mark) on the same line, that is, at the same position in the sub-scanning direction. Thereby, it is possible to reduce the range occupied by each nozzle identification mark on the inspection sheet 200.

[0048] The detection unit 133 detects each of the nozzle identification marks 231 to 238. Here, the processing of the detection unit 133 will be described. The detection of the nozzle identification marks 231 to 238 is performed by pattern matching with the image data (reference identification marks) of the nozzle identification marks previously stored in the non-volatile memory 14. In the pattern matching, the detection unit 133 sets a range of a predetermined number of pixels based on the upper left vertex as a comparison region in the scanned image, and while shifting the comparison region in pixel units, compares with the reference identification mark in each comparison region.

[0049] Specifically, the detection unit 133 performs a comparison of the pixel values (brightness) of the pixels corresponding to the comparison region and the reference identification mark. Then, the detection unit 133 calculates the total value of the absolute values of the differences of the respective pixel values (brightness) obtained by the comparison. In the case where the respective pixel values (brightness) are exactly the same, the total value of the differences theoretically becomes zero. The detection unit 133 calculates the matching rate based on the total value of the differences. The matching rate is a value that sets the case where the total value of the differences becomes zero to 100%, and decreases as the total value of the differences increases. Then, the detection unit 133 detects the comparison region where the matching rate is the maximum as an arbitrary range among the nozzle identification marks 231 to 238, and determines the center of the range as the nozzle identification mark position.

[0050] The detection unit 133 of the present embodiment determines the position of the nozzle inspection pattern 210 by using triangulation of the two nozzle identification marks included in the identification group. Thus, since the distance between the identification marks is relatively large by using the nozzle identification marks arranged in the left region 241 and the right region 242, the detection accuracy of the nozzle inspection pattern 210 can be improved.

[0051] If a set of identification marks is detected, the position of the nozzle inspection pattern 210 can be determined based on the positional relationship between the two nozzle identification marks included in the detected set of identification marks. However, when nozzle clogging occurs in any of the plurality of nozzles 301, it becomes impossible to accurately print the nozzle identification marks. Therefore, the multifunction machine 10 of the present embodiment prints a plurality of sets of identification marks through each nozzle group. As a result, even when nozzle clogging occurs in any nozzle group, as long as the set of identification marks is accurately printed by other nozzle groups, the nozzle inspection pattern 210 can be detected.

[0052] However, since any nozzle identification mark has the same size and the same shape, the detection unit 133 cannot distinguish which nozzle identification mark among the eight nozzle identification marks the detected nozzle identification mark is. Therefore, in the present embodiment, the printing positions of the respective nozzle identification marks are determined to be positions such that the distance between the two nozzle identification marks (distance between marks) included in each set of identification marks becomes a unique length. Therefore, the detection unit 133 can distinguish which nozzle identification mark has been detected based on the distance between marks.

[0053] Figure 5 A diagram showing the distances between marks for all combinations of the respective nozzle identification marks in the left region 241 and the respective nozzle identification marks in the right region 242. These distances between marks are registered in the nonvolatile memory 14 in a manner corresponding to the two nozzle identification marks corresponding thereto. In the present embodiment, the first A mark, the second A mark, the third A mark, and the fourth A mark are respectively arranged at positions 3, 5, 8, and 12 from the left, and the first B mark, the second B mark, the third B mark, and the fourth B mark are respectively arranged at positions 51, 49, 46, and 42 from the left. As a result, the distance between marks between the first A mark and the first B mark becomes 48.

[0054] In addition, the distance between marks between the second A mark and the second B mark is 44, the distance between marks between the third A mark and the third B mark is 38, and the distance between marks between the fourth A mark and the fourth B mark is 30. These distances between marks are different from the distances between marks of any other two nozzle identification marks. Further, for example, the distance between marks between the third A mark and the first B mark is 43, which is equal to the distance between marks between the first A mark and the third B mark. Thus, the distance between marks of two nozzle identification marks other than the set of identification marks corresponding to each nozzle group may also be equal to the distance between marks of other two nozzle identification marks.

[0055] Thus, in the present embodiment, the distance between the identifications of the two nozzle identifications included in each identification group in the inspection sheet 200 is set to a unique length. More specifically, the distance between the identifications of the two nozzle identifications in each identification group is different from the distance between any other two nozzle identifications. Thereby, the detection unit 133 can identify which nozzle identification has been detected based on the distance between the identifications.

[0056] Figure 6 And Figure 7 is an explanatory diagram of the detection process for the identification group. For example, as Figure 6 shown, it is assumed that the first, second nozzles and the fifth to twelfth nozzles are blocked. In this case, as Figure 6 shown, the first A identification and the first B identification are printed halfway. In addition, the second A identification, the second B identification, the third A identification, and the third B identification are not printed. The fourth A identification and the fourth B identification are printed normally. And in the matching performed by the detection unit 133, as Figure 6 shown, the matching rate becomes 50% in the first A identification and 49% in the first B identification. The matching rates of the second A identification, the second B identification, the third A identification, and the third B identification are all 0%. The matching rate of the fourth A identification is 99%, and the matching rate of the fourth B identification is 98%. When the recognition accuracy (threshold) available for position detection in the nozzle inspection pattern 210 is set to 60% or more, the only available identification group is the fourth identification group.

[0057] In this case, the detection unit 133 can obtain the distance 30 between the identifications based on the detection positions of the two nozzle identifications. As Figure 7 shown, the only identification group for which the distance between the identifications becomes 30 is the fourth identification group of the fourth A identification and the fourth B identification. Therefore, the detection unit 133 identifies that the detected nozzle identifications are the fourth A identification and the fourth B identification based on the positions between the identifications.

[0058] Next, a production method of the multifunction machine 10 as a printing apparatus will be described. In the production method of the present embodiment, by performing adjustment using the inspection pattern on the pre-adjustment (uncompleted) multifunction machine 10, the adjusted multifunction machine 10 can be produced. Here, in the uncompleted multifunction machine 10, although mechanical components and electrical components can be assembled to perform the printing operation, no adjustment related to printing has been performed. Through this production method, adjustment related to printing can be performed, and thus a finished product of the multifunction machine 10 can be obtained. In addition, this production method is implemented as part of the production process in the factory or is implemented after the installation of the uncompleted multifunction machine 10 at the customer's site.

[0059] The production method includes an inspection sheet printing process and an inspection sheet reading process. Figure 8It is a flowchart showing the inspection sheet printing process. Figure 9 It is a flowchart showing the inspection sheet reading process. As Figure 8 shown, in the inspection sheet printing process, first, paper is supplied to the multi-function machine 10 by the user (step S100). Next, various markings on the inspection sheet 200 are printed by the printing unit 11 of the unfinished multi-function machine 10 (step S102), and various inspection patterns on the inspection sheet 200 are printed by the printing unit 11 (step S104). In addition, the printing of various markings and various inspection patterns is sequentially performed from the upper part of the paper along the sub-scanning direction according to the conveyance of the medium while the print head 111 moves in the main scanning direction. Thus, the printing of the inspection sheet is completed.

[0060] Next, while referring to Figure 9 the inspection sheet reading process will be described. The user places the inspection sheet on the glass surface 121 and performs a user operation for starting the scan. In response to this, the scan control unit 132 starts driving the scan unit 12 and reads the upper part of the inspection sheet 200 (step S200). Here, the upper part refers to a range that is preset to include the positions of the nozzle markings 231 to 238, and also refers to a range that is preset in the sub-scanning direction of the scan unit 12.

[0061] Next, in the scan image obtained in step S200, the detection unit 133 detects the nozzle markings in the left region 241 (step S202). Specifically, the detection unit 133 detects the nozzle markings within the range of the left half of the scan image read in step S200. Next, in the scan image obtained in step S200, the detection unit 133 detects the nozzle markings in the right region 242 (step S204). Specifically, the detection unit 133 detects the nozzle markings within the range of the right half in the main scanning direction of the scan image read in step S200.

[0062] Next, in step S206, the detection unit 133 determines whether at least one or more nozzle markings have been successfully detected in each of the left region 241 and the right region 242 (step S206). In addition, when the matching rate is equal to or higher than a threshold value (for example, 60%), the detection unit 133 determines that the nozzle markings have been successfully detected.

[0063] When one or more nozzle identification marks cannot be detected in at least one of the left region 241 and the right region 242 (No in step S206), the process is aborted. In this case, since there is a possibility that the inspection sheet is upside down or reversed, the processor 13 notifies the user of an error in the UI unit 15.

[0064] When one or more nozzle identification marks have been successfully detected in any one of the left region 241 and the right region 242 (Yes in step S206), the detection unit 133 calculates the distance between the marks for all combinations of the nozzle identification marks in the left region 241 and the nozzle identification marks in the right region 242 (step S208).

[0065] Next, the detection unit 133 confirms whether there is a unique length among the calculated distances between the marks. For example, in the example described with reference to Figure 4 、 Figure 5 the distances of 48, 44, 38, and 30 are the unique lengths. When the distance between the marks with a unique length is obtained, it can be determined that the two detected nozzle identification marks are a mark group corresponding to the unique length. When there is no unique length (No in step S210), since the detection unit 133 fails to detect the nozzle identification marks and thus cannot detect the nozzle inspection pattern 210, the process is aborted.

[0066] When there is a unique length (Yes in step S210), the detection unit 133 selects the mark group with the longest distance between the marks (step S212). Next, the detection unit 133 determines the position of the nozzle inspection pattern 210 based on the detection positions of the two nozzle identification marks included in the mark group selected in step S212 (step S214). The relative positional relationship between the two nozzle identification marks in all the mark groups (four mark groups in the example of Figure 4 、 5 ) and the nozzle inspection pattern 210 has been preset in advance. Then, the detection unit 133 determines the position (range) of the nozzle inspection pattern 210 by referring to this positional relationship and based on the detection positions of the two nozzle identification marks.

[0067] Thus, in the present embodiment, since the detection unit 133 determines the position of the nozzle inspection pattern 210 using the mark group with the longest distance between the marks, the position determination of the nozzle inspection pattern can be performed more accurately.

[0068] Next, the detection unit 133 detects the nozzle inspection pattern 210 by reading the position determined in step S214 (step S216). Next, the adjustment unit 134 adjusts the nozzle 301 based on the detection result of the nozzle inspection pattern 210 (step S218).

[0069] Specifically, the adjustment unit 134 causes the cleaning unit 17 to perform the cleaning process of the nozzle 301 according to the matching result between the nozzle inspection pattern 210 and the reference pattern that has been preset corresponding to the nozzle inspection pattern 210. Specifically, when the matching rate with the nozzle inspection pattern is equal to or higher than the first threshold, the adjustment unit 134 determines that cleaning does not need to be performed. When the matching rate is less than the first threshold and equal to or higher than the second threshold, the adjustment unit 134 causes the cleaning unit 17 to perform cleaning with a lower intensity. In addition, when the matching rate is less than the second threshold, the adjustment unit 134 causes the cleaning unit 17 to perform cleaning with a higher intensity. Here, the second threshold is a value smaller than the first threshold. In addition, when the cleaning intensity is higher, the suction force becomes larger than when the intensity is lower. Since the nozzle inspection pattern 210 cannot be accurately printed when the degree of nozzle clogging is large, the matching rate decreases. Therefore, in this way, the adjustment unit 134 causes the cleaning unit 17 to clean the nozzle with an intensity corresponding to the matching rate, that is, an intensity corresponding to the nozzle clogging condition.

[0070] Next, the processor 13 performs other adjustment processes by reading other inspection patterns 221 to 223 while using the position inclination identifiers 261 to 274 (step S220). In the other adjustment processes, the processor 13 generates adjustment parameters for the printing unit 11 based on the detection results of the other inspection patterns 221 to 223 and stores the adjustment parameters in the non-volatile memory 14. In this way, the adjustment of the multifunction machine 10 is completed, and the production of the adjusted multifunction machine 10 is completed.

[0071] As described above, even when nozzle clogging occurs in some of the nozzles, the multifunction machine 10 of the present embodiment can reliably detect the nozzle inspection pattern. Moreover, by setting the shapes of the nozzle identifiers used for detecting the nozzle inspection pattern to the same size and the same shape, the matching process can be speeded up. Moreover, by setting the distance between the identifiers in each identifier group to a unique length, it is possible to distinguish which identifier group the two detected nozzle identifiers belong to.

[0072] A first modification of the first embodiment will be described. Although in the first embodiment, each nozzle group includes nozzles that are different from each other, one nozzle may be included in multiple nozzle groups. For example, it may be set that the first to fifth nozzles are included in the first nozzle group, the fifth to ninth nozzles are included in the second nozzle group, the ninth to thirteenth nozzles are included in the third nozzle group, and the twelfth to sixteenth nozzles are included in the fourth nozzle group.

[0073] As a second modification, although in the present embodiment, it is set that multiple nozzles are divided into four nozzle groups and four identification groups are printed on the inspection sheet, the number of divisions of the nozzles is not limited to the embodiment. As long as multiple nozzles are divided into two or more nozzle groups and two or more identification groups are printed. That is, it may be set that multiple nozzles are divided into three nozzle groups and three identification groups are printed, or it may be set that multiple nozzles are divided into five or more nozzle groups and five or more identification groups are printed.

[0074] Second Embodiment

[0075] Next, regarding the multifunction machine 10 according to the second embodiment, the differences from the multifunction machine 10 according to the first embodiment will be mainly described. The print head 111 of the multifunction machine 10 according to the second embodiment includes nozzle rows corresponding to four color inks of CMYK (C: cyan, M: magenta, Y: yellow, K: black), respectively, and performs printing in an inkjet manner.

[0076] Figure 10 It is an explanatory diagram of the nozzle rows and nozzle identification for each color in the second embodiment. In the second embodiment, on the inspection sheet 200, first nozzle identification 281 to 288 are printed using K ink in the same manner as in the first embodiment. In addition, second nozzle identification 291 to 298 formed by synthetic black are printed using C ink, M ink, and Y ink. First nozzle identification 281 to 284 and second nozzle identification 291 to 294 are printed in the left region 241. First nozzle identification 285 to 288 and second nozzle identification 295 to 298 are printed in the right region 242.

[0077] First nozzle identification 281 to 288 are an example of the first identification, and second nozzle identification 291 to 298 are an example of the second identification. In addition, second nozzle identification 291 to 298 only need to be an identification printed using at least one color identification.

[0078] The first nozzle identification marks 281 to 288 formed by K ink are all in the shape of double circles with the centers not coated with ink, and are identification marks of the same size and the same shape. In addition, the second nozzle identification marks 291 to 298 formed by color ink are all identification marks of the same size and the same shape with a blackened circle arranged at the center and a circle arranged around it. The second nozzle identification mark 291 formed by color ink is an identification mark of such a shape that when the first nozzle identification mark 281 printed with K ink is aligned with the center position, the ink-coated area does not overlap with the first nozzle identification mark 281.

[0079] In addition, the second nozzle identification mark 291 only needs to be in a shape that coats ink in the area where the ink is not coated in the first nozzle identification mark 281 when the first nozzle identification mark 281 printed with K ink is aligned with the center position, and it is not limited to the embodiment. For example, the second nozzle identification mark 291 may also have a part that overlaps with the first nozzle identification mark 281. For example, the second nozzle identification mark 291 may also be a double circle in the shape of a triangle.

[0080] In this embodiment, the multiple nozzles included in each color nozzle row are also divided into four nozzle groups, namely the first nozzle group to the fourth nozzle group. And the first nozzle identification mark 281 (the first A mark) and the first nozzle identification mark 288 (the first B mark) are printed with the K ink of the first nozzle group 321. Then, the second nozzle identification marks 291 and 298 for synthesizing black are printed with the C ink, M ink, and Y ink of the first nozzle group 321. Hereinafter, the second nozzle identification marks 291 and 298 are respectively referred to as the fifth A mark and the fifth B mark, and they are called the fifth mark group. Similarly, the first nozzle identification mark 282 (the second A mark) and the first nozzle identification mark 287 (the second B mark) are printed with the K ink of the second nozzle group 322. Then, the second nozzle identification marks 292 and 297 for synthesizing black are printed with the C ink, M ink, and Y ink of the second nozzle group 322. Hereinafter, the second nozzle identification marks 292 and 297 are respectively referred to as the sixth A mark and the sixth B mark, and they are called the sixth mark group.

[0081] The K ink of the third nozzle group 323 is used to print the first nozzle identification 283 (third A identification) and the first nozzle identification 286 (third B identification). Then, the C ink, M ink, and Y ink of the third nozzle group 323 are used to print the second nozzle identifications 293 and 296 for synthesizing black. Hereinafter, the second nozzle identifications 293 and 296 are respectively referred to as the seventh A identification and the seventh B identification, and they are referred to as the seventh identification group. The K ink of the fourth nozzle group 324 is used to print the first nozzle identification 284 (fourth A identification) and the first nozzle identification 285 (fourth B identification). Then, the C ink, M ink, and Y ink of the fourth nozzle group 324 are used to print the second nozzle identifications 294 and 295 for synthesizing black. Hereinafter, the second nozzle identifications 294 and 295 are respectively referred to as the eighth A identification and the eighth B identification, and they are referred to as the eighth identification group.

[0082] In the present embodiment, the printing unit 11 prints the two nozzle identifications included in the same identification group in the same cycle. In addition, the printing unit 11 prints all the identification groups at the same position in the same row, that is, at equal positions in the sub-scanning direction.

[0083] Moreover, the fifth A identification and the fifth B identification are printed at positions that are a fixed distance to the right from the first A identification and the first B identification, respectively. Similarly, the sixth A identification and the sixth B identification are printed at positions that are a fixed distance to the left from the second A identification and the second B identification, respectively. Moreover, the seventh A identification and the seventh B identification are printed at positions that are a fixed distance to the right from the third A identification and the third B identification, and the eighth A identification and the eighth B identification are printed at positions that are a fixed distance to the right from the fourth A identification and the fourth B identification, respectively.

[0084] FIG. 11 is a diagram showing the distances between the identifications. FIG. 11(a) shows the distances between the first nozzle identifications 281 to 288 printed using the K ink. FIG. 11(b) shows the distances between the second nozzle identifications printed using the color ink. In the present embodiment, the distances between the identifications of the first identification group to the fourth identification group are all of a unique length. And, as shown in FIG. 11(b), the second nozzle identifications 291 to 298 for synthesizing black are also set such that the distances between the identifications of the fifth identification group to the eighth identification group are all of a unique length.

[0085] That is, the distance between the identification marks of two first nozzle identification marks in the first to fourth identification groups is different from the distance between the identification marks of any other two first nozzle identification marks formed by K ink. In addition, the distance between the identification marks of two second nozzle identification marks in the fifth to eighth identification groups is different from the distance between the identification marks of any other two second nozzle identification marks formed by color ink. Thus, the detection unit 133 can identify which nozzle identification mark is detected based on the distance between the identification marks. In addition, as in the case of the distance between the identification marks of the first identification group and the fourth identification group, the distance between the identification marks can be equal even in the case of identification marks with different shapes.

[0086] Moreover, in the present embodiment, the detection unit 133 performs the detection of the first nozzle identification marks 281 to 288 formed by K ink, obtains the distance between the identification marks based on the detection result, and when a unique length is obtained, detects the nozzle inspection pattern 210 based on the unique length. And when the detection unit 133 successfully detects the nozzle inspection pattern 210 based on the first nozzle identification marks 281 to 288 formed by K ink, the detection unit 133 does not perform the detection or matching process of the second nozzle identification marks 291 to 298 formed by color ink. On the other hand, when the detection unit 133 fails to detect the nozzle inspection pattern 210 based on the first nozzle identification marks 281 to 288 formed by K ink, the detection unit 133 performs the detection of the second nozzle identification marks 291 to 298 formed by color ink, and obtains the distance between the identification marks based on the detection result. And when a unique length is obtained, the detection unit 133 detects the nozzle inspection pattern 210 based on the unique length. Thus, the nozzle inspection pattern 210 can be effectively detected.

[0087] Figure 12 And FIG. 13 is an explanatory diagram of the detection process of the identification group. For example, as Figure 12 shown, it is assumed that the second A identification mark, the second B identification mark, the fourth A identification mark, and the fourth B identification mark are detected. In this case, 39, 46, and 32 are obtained as the distances between the identification marks. Among them, since the unique lengths are 46 and 32, it can be identified that the corresponding second identification group and the fourth identification group are detected. In addition, the two identification groups can identify which is the second identification group and which is the fourth identification group based on the positional relationship between the two groups. Then, the nozzle inspection pattern 210 is detected using the second identification group with the longest distance between the identification marks. In addition, although the seventh A identification mark and the seventh B identification mark are also printed in the example Figure 12 shown, since the second identification group and the fourth identification group are detected, the detection of these identification marks such as the seventh A identification mark and the seventh B identification mark is not performed.

[0088] In addition, the structures and processes of the multifunction machine 10 according to the second embodiment, other than those described above, are the same as the structures and processes of the multifunction machine 10 according to the first embodiment.

[0089] A modified example of the second embodiment will be described. As Figure 14 shown, the print head 111 includes one nozzle row for K ink and one nozzle row for CMY color inks. In the case of having such a print head 111, the nozzle row is divided into a first nozzle group 331, a second nozzle group 332, and a third nozzle group 333. The first nozzle group 331 includes the first to fourth nozzles for K ink and four nozzles for Y ink. The second nozzle group 332 includes the fifth to eighth nozzles for K ink and four nozzles for M ink. The third nozzle group 333 includes the ninth to twelfth nozzles for K ink and four nozzles for C ink.

[0090] And, the first A mark and the first B mark are printed using the K ink of the first nozzle group 331. Next, the second A mark and the second B mark are printed using the K ink of the second nozzle group 332, and the third A mark and the third B mark are printed using the K ink of the third nozzle group 333. On the other hand, the fourth A mark and the fourth B mark are printed using the Y mark of the first nozzle group 331, the M mark of the second nozzle group 332, and the C mark of the third nozzle group 333.

[0091] The above embodiments are an example for implementing the present invention, and various other embodiments can also be adopted. For example, applying a modified example of a certain embodiment to other embodiments, etc., within the scope of the gist of the present invention described in the claims, various modifications and changes can be made.

[0092] Moreover, the present invention can also be applied as a program or method executed by a computer. In addition, there are cases where it is implemented as a separate device as described above, and there are also cases where it is implemented using components provided in multiple devices, including various modes. In addition, appropriate changes such as part being software and part being hardware can be made. In addition, the invention is also established as a recording medium for a program that controls a system. Of course, the recording medium for this program can be a magnetic recording medium or a semiconductor memory, and any recording medium developed in the future can be considered in exactly the same way.

[0093] Reference Signs

[0094] 10... Multifunction machine; 11... Printing unit; 12... Scanning unit; 13... Processor; 24... Non-volatile memory; 15... UI unit; 16... Communication unit; 17... Cleaning unit; 131... Printing control unit; 132... Scanning control unit; 133... Detection unit; 134... Adjustment unit.

Claims

1. A method for producing a printing device, comprising causing a pre-adjustment printing device of a serial inkjet method to print an inspection sheet including an inspection pattern, causing a scanner to read the inspection sheet, and adjusting the pre-adjustment printing device based on the inspection pattern detected by analyzing the read inspection sheet, thereby producing an adjusted printing device, wherein: The first A mark and the first B mark are printed on the inspection sheet by using the first nozzle group, and the second A mark and the second B mark are printed by using the second nozzle group, The distance between the first A marker and the first B marker is different from the distance between any two markers other than the combination of the first A marker and the first B marker. The distance between the second A marker and the second B marker is different from the distance between any two markers other than the combination of the second A marker and the second B marker. In the analysis, which mark is detected is identified based on the distance between the two marks detected on the inspection sheet, The position of the inspection pattern on the inspection sheet is determined based on the positions of the two identified markers.

2. The method for producing a printing device according to claim 1, wherein: Nozzles ejecting the same type of ink are divided into three or more nozzle groups including the first nozzle group and the second nozzle group. Each nozzle group is made to print two logos. The distance between two marks printed by each nozzle group is different from the distance between any two marks other than the combination of two marks printed by each nozzle group.

3. The method for producing a printing device according to claim 1, wherein: Each nozzle group includes nozzles that are different from each other.

4. The method for producing a printing device according to claim 1, wherein: The first A mark and the first B mark are printed on an end side of the inspection sheet relative to the inspection pattern.

5. The method for producing a printing device according to claim 4, wherein: The second A mark and the second B mark are printed on the end side of the inspection sheet relative to the inspection pattern.

6. The method for producing a printing device according to claim 1, wherein: The first A mark and the first B mark are printed in the same cycle.

7. The method for producing a printing device according to claim 6, wherein: The second A mark and the second B mark are printed in the same cycle.

8. The method for producing a printing device according to claim 1, wherein: The first A mark and the second A mark are printed at the same position in the sub-scanning direction.

9. The method for producing a printing device according to claim 1, wherein: The inspection pattern includes a nozzle inspection pattern indicating a clogging condition of a nozzle, The adjustment of the printing device includes cleaning the nozzle at an intensity corresponding to the clogging state of the nozzle.

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